// 5
package main

import (
	"fmt"
)

func main() {
	m := 1
	for i := 1; i <= 20; i++ {
		m = multiple(m, i)
	}
	fmt.Println(m)
}
func multiple(a, b int) int {
	m := a * b
	for b != 0 {
		a, b = b, a%b
	}
	return m / a
}
